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smoothly and slowly.
used to compensate, the vertical component of lift is
reduced significantly and a rapid descent will ensue as
the turn progresses.
Common Errors for Level Turns
• Failure to adequately clear the area before
beginning the turn.
• Attempting to sit up straight, in relation to the
ground, during a turn, rather than maintaining
posture with the cart.
• Insufficient feel for the PPC.
• Gaining proficiency in turning in only one
direction; not practicing turns in both directions.
• Failure to coordinate the throttle with the
steering controls.
• Altitude gain/loss during the turn.
• Too great of a bank angle.
Climbs and Climbing Turns, Descents
and Descending Turns
To gain altitude, increase engine RPM. To lose altitude,
decrease engine RPM. When a PPC enters a
climb, it changes flight path from level or descending
(with level or declined planes) to ascending with an
inclined plane. [Figure 6-7]
Straight climbs are achieved by increasing throttle
above the level flight setting and holding a straight
heading. Climbing turns require more throttle than
straight climbs.
During any descent, the pilot must clear the area below
and to the turning side (if applicable) before beginning
these maneuvers.
Figure 6-7. When a PPC stabilizes in a climb or descent, the flight path is a declined or inclined plane.
6-8
To descend, reduce throttle below the straight and
level RPM while flying straight or in a turn.
Throttle reduction is the basis for determining the
descent rate. Banking the aircraft will also increase
the descent rate. Greater bank angles result in greater
descent rates.
Gliding
A glide is a basic maneuver in which the PPC loses
altitude in a controlled descent with little or no engine
power.
The PPC glide ratio is the distance the aircraft will
travel forward in relation to the altitude it loses. For
instance, if the aircraft travels 3,000 feet forward while
descending 1,000 feet, its glide ratio is said to be 3 to
1. Wind is a major influence on the gliding distance
in relationship to the PPC movement over the ground.
With a tailwind, the PPC will glide farther, perhaps a
5 to 1 glide ratio because of the higher groundspeed.
Conversely, with a headwind or a crosswind, the aircraft
will not glide as far, perhaps a 2 to 1 glide ratio,
because of the slower groundspeed.
Typically, a PPC is designed to fly efficiently near the
best lift to drag ratio. Adding flare will normally decrease
your speed by increasing your drag and angle
of attack, reducing your glide ratio. Do not attempt to
“stretch” a glide by applying flare and reducing the
airspeed. Attempts to stretch a glide will invariably
result in an increase in the descent rate and angle of
descent.
A stabilized power-off descent is referred to as a normal
glide. The flight instructor, while demonstrating a
normal glide, should direct the pilot to note:
• sounds made by the PPC,
• no steering control is required except to
maintain intended direction, and
• feel of the powered parachute.
Wing Trim
The powered parachute is designed so there is no
pressure needed on the flight steering controls, thus,
no pulling on the trailing edge when the PPC is flying
along normally. If properly trimmed, the PPC will fly
straight with no pilot input except for slight variations
due to left-turning tendencies. If the PPC is flying out
of this basic balanced condition, one of the steering
controls can be pulled down and slight pressure
applied on the side to reduce the speed of the faster
side wing with a trim lock to temporarily relieve the
pilot of constant steering input. This trim lock is a
mechanical device the pilot can set on the ground or
in flight. [Figure 6-8] It holds the pressure on the side
that needs it so the pilot does not have to continually
apply pressure. Due to the inefficiency of increased
drag, the constant use of trim locks should not be a
replacement for a well set up and properly trimmed
wing. Most PPCs are currently not equipped with trim
locks but this will depend on the specific manufacturer
and make/model. An improperly-trimmed PPC can
quickly produce pilot tension and fatigue, requiring
constant pressure on one of the steering bars.
Figure 6-8. The right trailing edge is pulled down slightly
using the trim system, to correct for the left-turning
tendency.
7-1
Most powered parachute incidents occur during the
takeoff. This is because unlike most other types of aircraft,
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Powered Parachute Flying Handbook动力伞飞行手册(56)
